Select the best way to revise the following sentence to achieve​ gender-neutral, unbiased language while avoiding problems with pronoun agreement.
An elementary school teacher may need to alert her​ students' parents about the presence of head lice.
A.
No change is​ needed; the sentence is fine as it is.
B.
An elementary school teacher may need alert​ students' parents about the presence of head lice.
C.
An elementary school teacher who realizes that one of her students has head lice may need to alert​ students parents to the problem.
D.
When an elementary school teacher realizes that a child has head​ lice, she may need to alert her​ students' parents to the problem.